Geological Time Review

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Across
  1. 2. The study of rock strata
  2. 4. Produces geological structures such as folds, joints, faults
  3. 8. Cenozoic Era is also known as the age of the ______
  4. 9. This Eon is divided into 3 eras
  5. 10. This era is divided into the Tertiary and Quaternary periods
  6. 11. Ancient cores of the continents
  7. 13. When rock layers are located in different places, they are matched up by _________
  8. 15. A gap between rocks of very different ages, often marked by an erosional surface
  9. 17. Earth's history is recorded on the _____Time Scale
  10. 19. The comparison of one rock or fossil to another to determine which one is older or younger is called ______age.
  11. 21. This era is divided into the Triassic, Jurassic, and Cretaceous periods
Down
  1. 1. The lowest layers are the oldest and the higher layers are the youngest
  2. 3. Cyanobacteria, responsible for adding oxygen to the atmosphere
  3. 5. The earliest crust was probably made from this
  4. 6. One of the eras in the Phanerozoic eon
  5. 7. One of the eras in the Phanerozoic eon
  6. 11. This is the era we live in now
  7. 12. Common index fossils
  8. 14. This mass extinction occurred 65 mya in the Mesozoic Era
  9. 16. Longest portions of geological time
  10. 18. _____ beds is an example of the iridium layer that was deposited at the time of the Cretaceous-Tertiary extinctions
  11. 20. This type of fossil must be distinctive, widespread, and short-lived